An-Najah Staff

In this study, olive oil samples of different storage ages and locations in Palestine were studied. The density, refractive index, acidity and viscosity of the samples were measured. The acidity of olive oil samples from different locations and different crops showed that acidity increases as a function of storage age. Most of olive oil samples (storage age ≤ 12 years) acidity did not exceed the international quality standards (< 3.3%). It is worth noting that olive oil can be stored until 12 years without exceeding the international quality standards of acidity. The refractive index of the olive oil samples were studied against storage and results showed that the refractive index decreases as a function of storage age.The viscosity of olive oil samples of 2012 crop from different locations was studied, and the results showed that most of the olive oil samples are classified to be extra- virgin.Two and three constant formulas were proposed to obtain more suitable prediction of temperature dependence of dynamic viscosity of olive oi